The Spanish conquest of Yucatán was the campaign undertaken by the Spanish conquistadores against the Late Postclassic Maya states and polities in the Yucatán Peninsula, a vast limestone plain covering south-eastern Mexico, northern Guatemala, and all of Belize. The Spanish conquest of the Yucatán Peninsula was hindered by its politically fragmented state. The Spanish engaged in a strategy of concentrating native populations in newly founded colonial towns. Native resistance to the new nucleated settlements took the form of the flight into inaccessible regions such as the forest or joining neighbouring Maya groups that had not yet submitted to the Spanish. Among the Maya, ambush was a favoured tactic. Spanish weaponry included broadswords, rapiers, lances, pikes, halberds, crossbows, matchlocks and light artillery. Maya warriors fought with flint-tipped spears, bows and arrows and stones, and wore padded cotton armour to protect themselves. The Spanish introduced a number of Old World diseases previously unknown in the Americas, initiating devastating plagues that swept through the native populations.
The first encounter with the Yucatán Maya occurred in 1502, when the fourth voyage of Christopher Columbus came across a large Maya trading canoe off Honduras. In 1517, Francisco Hernández de Córdoba made landfall on the tip of the peninsula. His expedition continued along the coast and suffered heavy losses in a pitched battle at Champotón, forcing a retreat to Cuba. Juan de Grijalva explored the coast in 1518, and heard tales of the wealthy Aztec Empire further west. As a result of these rumours, Hernán Cortés set sail with another fleet. From Cozumel he continued around the peninsula to Tabasco where he fought a battle at Potonchán; from there Cortés continued onward to conquer the Aztec Empire. In 1524, Cortés led a sizeable expedition to Honduras, cutting across southern Campeche, and through Petén in what is now northern Guatemala. In 1527 Francisco de Montejo set sail from Spain with a small fleet. He left garrisons on the east coast, and subjugated the northeast of the peninsula. Montejo then returned to the east to find his garrisons had almost been eliminated; he used a supply ship to explore southwards before looping back around the entire peninsula to central Mexico. Montejo pacified Tabasco with the aid of his son, also named Francisco de Montejo.
In 1531 the Spanish moved their base of operations to Campeche, where they repulsed a significant Maya attack. After this battle, the Spanish founded a town at Chichen Itza in the north. Montejo carved up the province amongst his soldiers. In mid-1533 the local Maya rebelled and laid siege to the small Spanish garrison, which was forced to flee. Towards the end of 1534, or the beginning of 1535, the Spanish retreated from Campeche to Veracruz. In 1535, peaceful attempts by the Franciscan Order to incorporate Yucatán into the Spanish Empire failed after a renewed Spanish military presence at Champotón forced the friars out. Champotón was by now the last Spanish outpost in Yucatán, isolated among a hostile population. In 1541-42 the first permanent Spanish town councils in the entire peninsula were founded at Campeche and Mérida. When the powerful lord of Mani converted to the Roman Catholic religion, his submission to Spain and conversion to Christianity encouraged the lords of the western provinces to accept Spanish rule. In late 1546 an alliance of eastern provinces launched an unsuccessful uprising against the Spanish. The eastern Maya were defeated in a single battle, which marked the final conquest of the northern portion of the Yucatán Peninsula.
The polities of Petén in the south remained independent and received many refugees fleeing from Spanish jurisdiction. In 1618 and in 1619 two unsuccessful Franciscan missions attempted the peaceful conversion of the still pagan Itza. In 1622 the Itza slaughtered two Spanish parties trying to reach their capital Nojpetén. These events ended all Spanish attempts to contact the Itza until 1695. Over the course of 1695 and 1696 a number of Spanish expeditions attempted to reach Nojpetén from the mutually independent Spanish colonies in Yucatán and Guatemala. In early 1695 the Spanish began to build a road from Campeche south towards Petén and activity intensified, sometimes with significant losses on the part of the Spanish. Martín de Urzúa y Arizmendi, governor of Yucatán, launched an assault upon Nojpetén in March 1697; the city fell after a brief battle. With the defeat of the Itza, the last independent and unconquered native kingdom in the Americas fell to the Spanish.